Socioeconomic inequalities in dental caries among 5-year-olds in four Chinese provinces.

OBJECTIVE To explore socioeconomic inequalities in dental caries among 5-year-olds in four Chinese provinces. METHODS This study used data from 1,732 children living in Guangxi, Hubei, Jilin and Shanxi who participated in the Third National Oral Health Survey in 2005. Questionnaires were completed by parents to collect information on family socioeconomic position (parental education and household income) and children's dental behaviours (toothbrushing frequency, sugar intake frequency and last dental visit). Children were clinically examined for dental caries, which was reported using the dmft index. Socioeconomic inequalities in children's caries experience were assessed in negative binomial regression models. RESULTS There were significant gradients in children's dmft by household income. Children's dmft increased from 2.63 in the highest income group to 4.70 in the lowest income group. However, parental education was not significantly related to childhood dental caries. CONCLUSION Clear social gradients in caries experience of deciduous teeth were found by household income but not parental education.